Enzyme Research最新文献_第7页

Esterase Active in Polar Organic Solvents from the Yeast Pseudozyma sp. NII 08165. 酵母假酶在极性有机溶剂中活性的酯酶。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-04-03 DOI: 10.1155/2014/494682

Deepthy Alex, Anju Shainu, Ashok Pandey, Rajeev K Sukumaran

{"title":"Esterase Active in Polar Organic Solvents from the Yeast Pseudozyma sp. NII 08165.","authors":"Deepthy Alex, Anju Shainu, Ashok Pandey, Rajeev K Sukumaran","doi":"10.1155/2014/494682","DOIUrl":"https://doi.org/10.1155/2014/494682","url":null,"abstract":"Esterases/lipases active in water miscible solvents are highly desired in biocatalysis where substrate solubility is limited and also when the solvent is desired as an acyl acceptor in transesterification reactions, as with the case of biodiesel production. We have isolated an esterase from the glycolipid producing yeast-Pseudozyma sp. NII 08165 which in its crude form was alkali active, thermo stable, halo tolerant and also capable of acting in presence of high methanol concentration. The crude enzyme which maintained 90% of its original activity after being treated at 70°C was purified and the properties were characterized. The partially purified esterase preparation had temperature and pH optima of 60°C and 8.0 respectively. The enzyme retained almost complete activity in presence of 25% methanol and 80% activity in the same strength of ethanol. Conditions of enzyme production were optimized, which lead to 9 fold increase in the esterase yield. One of the isoforms of the enzyme LIP1 was purified to homogeneity and characterized. Purified LIP1 had a K m and V max of 0.01 and 1.12, respectively. The purified esterase lost its thermo and halo tolerance but interestingly, retained 97% activity in methanol. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/494682","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32318193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Immobilization of Aspergillus niger F7-02 Lipase in Polysaccharide Hydrogel Beads of Irvingia gabonensis Matrix. 黑曲霉F7-02脂肪酶在加蓬树基质多糖水凝胶珠中的固定化。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-12-31 DOI: 10.1155/2014/967056

Safaradeen Olateju Kareem, Olayinka Quadri Adio, Michael Bamitale Osho

{"title":"Immobilization of Aspergillus niger F7-02 Lipase in Polysaccharide Hydrogel Beads of Irvingia gabonensis Matrix.","authors":"Safaradeen Olateju Kareem, Olayinka Quadri Adio, Michael Bamitale Osho","doi":"10.1155/2014/967056","DOIUrl":"https://doi.org/10.1155/2014/967056","url":null,"abstract":"The potential of polysaccharide Irvingia gabonensis matrix as enzyme immobilization support was investigated. Lipase of Aspergillus niger F7-02 was immobilized by entrapment using glutaraldehyde as the cross-linking agent and stabilized in ethanolic-formaldehyde solution. The pH and temperature stability and activity yield of the immobilized enzyme were determined. Such parameters as enzyme load, bead size, number of beads, and bead reusability were also optimized. Adequate gel strength to form stabilized beads was achieved at 15.52% (w/v) Irvingia gabonensis powder, 15% (v/v) partially purified lipase, 2.5% (v/v) glutaraldehyde, and 3 : 1 (v/v) ethanolic-formaldehyde solution. There was 3.93-fold purification when the crude enzyme was partially purified in two-step purification using Imarsil and activated charcoal. Optimum lipase activity 75.3 Ug(-1) was achieved in 50 mL test solution containing 15 beads of 7 mm bead size. Relative activity 80% was retained at eight repeated cycles. The immobilization process gave activity yield of 59.1% with specific activity of 12.3 Umg(-1) and stabilized at optimum pH 4.5 and temperature 55°C. Thus the effectiveness and cost-efficiency of I. gabonensis as a polymer matrix for lipase immobilization have been established. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/967056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32997448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Enhanced thermostability of a fungal alkaline protease by different additives. 不同添加剂对真菌碱性蛋白酶热稳定性的影响。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-07-03 DOI: 10.1155/2014/109303

Nilesh P Nirmal, R Seeta Laxman

引用次数: 16

Effect of Chromium(VI) Toxicity on Enzymes of Nitrogen Metabolism in Clusterbean (Cyamopsis tetragonoloba L.). 铬(VI)毒性对四季豆氮代谢酶的影响

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-03-18 DOI: 10.1155/2014/784036

Punesh Sangwan, Vinod Kumar, U N Joshi

引用次数: 0

Molecular Dynamics and Metadynamics Simulations of the Cellulase Cel48F. 纤维素酶Cel48F的分子动力学和元动力学模拟。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-05-21 DOI: 10.1155/2014/692738

Osmair Vital de Oliveira

{"title":"Molecular Dynamics and Metadynamics Simulations of the Cellulase Cel48F.","authors":"Osmair Vital de Oliveira","doi":"10.1155/2014/692738","DOIUrl":"https://doi.org/10.1155/2014/692738","url":null,"abstract":"Molecular dynamics (MD) and metadynamics techniques were used to study the cellulase Cel48F-sugar. Cellulase is enzyme that breaks cellulose fibers into small sugar units and is potentially useful in second generation alcohol production. In MD simulations, the overall structure of equilibrated Cel48F did not significantly change along the trajectory, retaining root mean square deviation below 0.15 nm. A set of 15 residues interacting with the sugar chains via hydrogen bonding throughout the simulation was observed. The free energy of dissociation (ΔGdiss.) of the chains in the catalytic tunnel of Cel48F was determined by metadynamics. The ΔGdiss. values of the chains entering and leaving the wild-type Cel48F cavity were 13.9 and 62.1 kcal/mol, respectively. We also mutated the E542 and Q543 to alanine residue and obtained ΔGdiss. of 41.8 and 45.9 kcal/mol, respectively. These mutations were found to facilitate smooth dissociation of the sugar chain across the Cel48F tunnel. At the entry of the Cel48F tunnel, three residues were mutated to alanine: T110, T213, and L274. Contrary to the T110A-Cel48F, the mutants T213-Cel48F and L274-Cel48F prevented the sugar chain from passing across the leaving site. The present results can be a guideline in mutagenesis studies to improve processing by Cel48F. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/692738","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32453134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Sequential Statistical Optimization of Media Components for the Production of Glucoamylase by Thermophilic Fungus Humicola grisea MTCC 352. 嗜热真菌腐霉MTCC 352产糖淀粉酶培养基组分的序列统计优化。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-07-09 DOI: 10.1155/2014/317940

Vinayagam Ramesh, Vytla Ramachandra Murty

{"title":"Sequential Statistical Optimization of Media Components for the Production of Glucoamylase by Thermophilic Fungus Humicola grisea MTCC 352.","authors":"Vinayagam Ramesh, Vytla Ramachandra Murty","doi":"10.1155/2014/317940","DOIUrl":"https://doi.org/10.1155/2014/317940","url":null,"abstract":"Glucoamylase is an industrially important enzyme which converts soluble starch into glucose. The media components for the production of glucoamylase from thermophilic fungus Humicola grisea MTCC 352 have been optimized. Eight media components, namely, soluble starch, yeast extract, KH2PO4, K2HPO4, NaCl, CaCl2, MgSO4 ·7H2O, and Vogel's trace elements solution, were first screened for their effect on the production of glucoamylase and only four components (soluble starch, yeast extract, K2HPO4, and MgSO4 ·7H2O) were identified as statistically significant using Plackett-Burman design. It was fitted into a first-order model (R (2) = 0.9859). Steepest ascent method was performed to identify the location of optimum. Central composite design was employed to determine the optimum values (soluble starch: 28.41 g/L, yeast extract: 9.61 g/L, K2HPO4: 2.42 g/L, and MgSO4 ·7H2O: 1.91 g/L). The experimental activity of 12.27 U/mL obtained was close to the predicted activity of 12.15. High R (2) value (0.9397), low PRESS value (9.47), and AARD values (2.07%) indicate the accuracy of the proposed model. The glucoamylase production was found to increase from 4.57 U/mL to 12.27 U/mL, a 2.68-fold enhancement, as compared to the unoptimized medium. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/317940","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32583945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Studies of inhibitory mechanisms of propeptide-like cysteine protease inhibitors. 前肽样半胱氨酸蛋白酶抑制剂抑制机制的研究。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-06-19 DOI: 10.1155/2014/848937

Bui T T Nga, Yuki Takeshita, Misa Yamamoto, Yoshimi Yamamoto

{"title":"Studies of inhibitory mechanisms of propeptide-like cysteine protease inhibitors.","authors":"Bui T T Nga, Yuki Takeshita, Misa Yamamoto, Yoshimi Yamamoto","doi":"10.1155/2014/848937","DOIUrl":"https://doi.org/10.1155/2014/848937","url":null,"abstract":"Mouse cytotoxic T-lymphocyte antigen-2α (CTLA-2α), Drosophila CTLA-2-like protein (crammer), and Bombyx cysteine protease inhibitor (BCPI) belong to a novel family of cysteine protease inhibitors (I29). Their inhibitory mechanisms were studied comparatively. CTLA-2α contains a cysteine residue (C75), which is essential for its inhibitory potency. The CTLA-2α monomer was converted to a disulfide-bonded dimer in vitro and in vivo. The dimer was fully inhibitory, but the monomer, which possessed a free thiol residue, was not. A disulfide-bonded CTLA-2α/cathepsin L complex was isolated, and a cathepsin L subunit with a molecular weight of 24,000 was identified as the interactive enzyme protein. Crammer also contains a cysteine residue (C72). Both dimeric and monomeric forms of crammer were inhibitory. A crammer mutant with Cys72 to alanine (C72A) was fully inhibitory, while the replacement of Gly73 with alanine (G73A) caused a significant loss in inhibitory potency, which suggests a different inhibition mechanism from CTLA-2α. BCPI does not contain cysteine residue. C-terminal region (L77-R80) of BCPI was essential for its inhibitory potency. CTLA-2α was inhibitory in the acidic pH condition but stabilized cathepsin L under neutral pH conditions. The different inhibition mechanisms and functional considerations of these inhibitors are discussed. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/848937","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32520872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Purification and Characterization of a Unique Pectin Lyase from Aspergillus giganteus Able to Release Unsaturated Monogalacturonate during Pectin Degradation. 巨曲霉在果胶降解过程中释放不饱和单半乳糖酸的独特果胶裂解酶的纯化与特性研究。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-12-31 DOI: 10.1155/2014/353915

Danielle Biscaro Pedrolli, Eleonora Cano Carmona

{"title":"Purification and Characterization of a Unique Pectin Lyase from Aspergillus giganteus Able to Release Unsaturated Monogalacturonate during Pectin Degradation.","authors":"Danielle Biscaro Pedrolli, Eleonora Cano Carmona","doi":"10.1155/2014/353915","DOIUrl":"https://doi.org/10.1155/2014/353915","url":null,"abstract":"A pectin lyase, named PLIII, was purified to homogeneity from the culture filtrate of Aspergillus giganteus grown in submerged culture containing orange peel waste as carbon source. PLIII was able to digest apple pectin and citrus pectins with different degrees of methyl esterification. Interestingly, the PLIII activity was stimulated in the presence of some divalent cations including Pb(2+) and was not significantly affected by Hg(2+). Like other pectin lyases, PLIII is stimulated by but is not dependent on Ca(2+). The main soluble product released during the degradation of pectic substances promoted by the PLIII is compatible with an unsaturated monogalacturonate. PLIII is a unique enzyme able to release unsaturated monogalacturonate as the only soluble product during the degradation of pectic substances; therefore, PLIII was classified as an exo-pectin lyase. To our knowledge, this is the first characterization of an exo-pectin lyase. The PLIII described in this work is potentially useful for ethanol production from pectin-rich biomass, besides other common applications for alkaline pectinases like preparation of textile fibers, coffee and tea fermentation, vegetable oil extraction, and the treatment of pulp in papermaking. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/353915","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33323620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 24

Optimisation of Cellulase Production by Penicillium funiculosum in a Stirred Tank Bioreactor Using Multivariate Response Surface Analysis. 基于多元响应面分析的搅拌槽生物反应器中真菌青霉产纤维素酶优化研究。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-06-25 DOI: 10.1155/2014/703291

Marcelle Lins de Albuquerque de Carvalho, Daniele Fernandes Carvalho, Edelvio de Barros Gomes, Roberto Nobuyuki Maeda, Lidia Maria Melo Santa Anna, Aline Machado de Castro, Nei Pereira

{"title":"Optimisation of Cellulase Production by Penicillium funiculosum in a Stirred Tank Bioreactor Using Multivariate Response Surface Analysis.","authors":"Marcelle Lins de Albuquerque de Carvalho, Daniele Fernandes Carvalho, Edelvio de Barros Gomes, Roberto Nobuyuki Maeda, Lidia Maria Melo Santa Anna, Aline Machado de Castro, Nei Pereira","doi":"10.1155/2014/703291","DOIUrl":"https://doi.org/10.1155/2014/703291","url":null,"abstract":"Increasing interest in the production of second-generation ethanol necessitates the low-cost production of enzymes from the cellulolytic complex (endoglucanases, exoglucanases, and β-glucosidases), which act synergistically in cellulose breakdown. The present work aimed to optimise a bioprocess to produce these biocatalysts from the fungus Penicillium funiculosum ATCC11797. A statistical full factorial design (FFD) was employed to determine the optimal conditions for cellulase production. The optimal composition of culture media using Avicel (10 g·L(-1)) as carbon source was determined to include urea (1.2 g·L(-1)), yeast extract (1.0 g·L(-1)), KH2PO4 (6.0 g·L(-1)), and MgSO4 ·7H2O (1.2 g·L(-1)). The growth process was performed in batches in a bioreactor. Using a different FFD strategy, the optimised bioreactor operational conditions of an agitation speed of 220 rpm and aeration rate of 0.6 vvm allowed the obtainment of an enzyme pool with activities of 508 U·L(-1) for FPase, 9,204 U·L(-1) for endoglucanase, and 2,395 U·L(-1) for β-glucosidase. The sequential optimisation strategy was effective and afforded increased cellulase production in the order from 3.6 to 9.5 times higher than production using nonoptimised conditions. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/703291","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32531300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 26

Assessment of serum enzymatic antioxidant levels in patients with recurrent aphthous stomatitis: a case control study. 评估复发性口腔炎患者血清酶抗氧化水平:一项病例对照研究。

Enzyme Research Pub Date : 2014-01-01 Epub Date: 2014-12-10 DOI: 10.1155/2014/340819

Ishita Gupta, Arvind Shetti, Vaishali Keluskar, Anjana Bagewadi

{"title":"Assessment of serum enzymatic antioxidant levels in patients with recurrent aphthous stomatitis: a case control study.","authors":"Ishita Gupta, Arvind Shetti, Vaishali Keluskar, Anjana Bagewadi","doi":"10.1155/2014/340819","DOIUrl":"https://doi.org/10.1155/2014/340819","url":null,"abstract":"Background and Aim. Recurrent aphthous stomatitis (RAS) is a common oral mucosal disorder characterized by recurrent, painful oral aphthae. Despite extensive research, the exact etiology of RAS remains elusive. Recently oxidant-antioxidant imbalance of the body has been implicated in the pathogenesis of recurrent aphthous stomatitis. Thus, the aim of the study was to evaluate the enzymatic antioxidant levels in patients with recurrent aphthous stomatitis. Materials and Methods. The serum levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were measured in 30 patients with recurrent aphthous stomatitis and compared to the control group, which included 30 healthy subjects. Student's t-test was performed for statistical evaluation. Results. The mean levels of superoxide dismutase (130.2 ± 15.94 U/mL) and glutathione peroxidase (3527.93 ± 488.32 U/L) were found to be significantly lower in study group as compared to control group (211.9 ± 20.93 U/mL, 8860.93 ± 1105.31 U/L, resp.) (P = 0.000) while level of catalase in study group was significantly higher when compared to control group (10981.00 ± 1018.07 U/mL versus 9764.00 ± 1621.19 U/mL) (P = 0.000). Conclusion. Enzymatic antioxidant system is impaired in recurrent aphthous stomatitis patients and seems to play a crucial role in its pathogenesis. ","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2014/340819","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32965298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 14